Motor-vehicle seat with backrest which can be swung forward out of a position of use

ABSTRACT

A vehicle passenger seat located adjacent to the driver is equipped with a backrest and can be swung past the dashboard of a motor vehicle by first pivoting the backrest forward, a rearward sliding movement being superimposed on the pivoting movement because a bracket receiving the backrest pivotably is provided with a guide device and a displacement of the bracket together with the backrest is produced by means of a supporting lever arrangement.

The present application is a continuation in part of my copendingapplication, Ser. No. 714,209 filed Mar. 21, 1985, now U.S. Pat. No.4,636,003 of Jan. 13, 1987.

The invention relates to a motor-vehicle seat with a backrest which canbe swung forward out of the position of use and which is mounted so asto be laterally pivotable on a bracket connected to the seat-cushionframe, there being a guide device by means of which, when the backrestis pivoted, the point of articulation of the backrest on the bracket isdisplaced in the longitudinal direction of the vehicle via a leverarrangement connected to the backrest.

A motor-vehicle seat of this type, in which, to make it easy to reachthe rear seats in a two-door passenger car when the backrest is swungforward, the entire seat is moved only temporarily in the direction ofthe dashboard, is known from German Auslegesschrift No. 1,013,535.However, because of the greatly restricted view to the right, it is notadvisable to maintain the tilted position during driving.

Particularly with regard to delivery vehicles provided with a seatadjacent to the driver and access to the loading space from the driver'scab, it is known to tilt the adjacent seat forward about a front pivotaxis, the seat underframe also being swung in at the same time, thusensuring a wide passage which allows even relatively large articles tobe loaded and unloaded from the co-driver's side. Seats of this typehave heretofore been used without headrests, so that, when the entireseat has been tilted, despite the fact that the backrest has come upagainst the dashboard, there has still been a sufficient passage widthand a good view to the right has been provided during driving. Sincesuch seats are now provided with headrests, these butt against the frontscreen even after a relatively small pivoting angle when the seat isswung forward, so that the passage width obtainable and the view to theright are impaired to an extent which is no longer acceptable.

The object of the invention is to provide a way in which it is possibleto use, in an operationally reliable way, seats adjacent to the driverequipped with headrests in vehicles of the type described, and to hingethem in such a way that, in the inoperative position of the seat, asufficiently large passage width is obtained, at the same time with theview to the right being improved substantially.

It is a further object of the invention to have a motor-vehicle seatwith a backrest which can be swung forward out of the position of useand which is mounted so as to be laterally pivotable on a bracketconnected to a seat-cushion frame, there being a guide device by meansof which the point of articulation of the backrest on the bracket isdisplaced in the longitudinal direction of the vehicle via a leverarrangement connected to the backrest, characterized in that the guidedevice is assigned to the bracket in such a way that the latter isarranged so as to be displaceable relative to the seat-cushion frame,and in that, when the backrest is pivoted out of the position of use,the backrest together with the bracket is moved to the rear via at leastone supporting lever articulated on the seat frame and fixed to thebackrest and wherein in the inoperative position forms, without theposition of the headrest having to be changed, the initial position forswinging the entire seat about a front pivot axis in the way known perse, the seat underframe at the same time being transferred into anextended position providing a passage width.

In a preferred exemplary embodiment of the invention, a guide device isdesigned as a slot which is made in a bracket and into which projects apivot pin assigned to the seat cushion and belonging to an associatedsupporting lever and a locking pin arranged at a distance from the pivotpin and intended for a locking lever which prevents a sliding movementof the bracket in the position of use of the seat and which is pivotableagainst spring force. In this way, the guide parts engaging into theslot are also used to perform bearing and supporting functions and serveas end stops.

It is a further object of the invention to have a motor-vehicle seatwith a backrest which can be swung forward out of the position of useand which is mounted so as to be laterally pivotable on a bracketconnected to a seat-cushion frame, having a guide device by means ofwhich the point of articulation of the backrest on the bracket isdisplaced in the longitudinal direction of the vehicle via a leverarrangement connected to the backrest, characterized in that the guidedevice is assigned to the bracket in such a way that the latter isarranged so as to be displaceable relative to the seat-cushion frame,and when the backrest is pivoted out of the position of use, thebackrest together with the bracket is moved to the rear via at least onesupporting lever consisting of two portions articulated to one anotherand to the seat frame and fixed to the backrest. The guide device beinga slot in the bracket and into which projects a pivot pin assigned tothe seat cushion belonging to the associated supporting lever and alocking pin for preventing sliding movement of the bracket in theposition of use of the seat arranged at a distance from the pivot pin,and further characterized in that a locking lever pivotable against aspring force, rigidly provided with an axially offset locking nose isbrought into resilient engagement with a pin connected to the backrest,when the backrest is transferred from the inoperative position into theposition of use, wherein the pivoting movements of the locking lever andof the locking nose are transmitted, via a shaft extending in thetransverse direction of the vehicle, to a mirror-image lockingarrangement on the other side of the seat.

These and other objects, features, and advantages of the presentinvention will become more apparent from the following description whentaken in connection with the accompanying drawings which show, for thepurposes of illustration only, two embodiments in accordance with thepresent invention, and wherein:

FIG. 1 shows a co-driver's side seat according to the invention in itsthree possible positions;

FIG. 2 shows the region of the guide device on a larger scale, in theoperating position of the seat;

FIG. 3 shows the region of the guide device, likewise on a larger scale,with the backrest swung down;

FIG. 4 is a second embodiment having a locking means, controlled via atoothed segment, of the bracket and of the locking lever at the base, inthe position of the use of the motor vehicle seat;

FIG. 5 is the arrangement according to FIG. 4 when the locking means isreleased and the backrest is partly swivelled forward;

FIG. 6 shows the arrangement according to FIG. 1 wherein the actuatinglever of the locking lever on one side of the seat activates a mirrorimage locking lever arrangement on the other side of the seat;

FIGS. 7 and 8 shows the spring mechanism of FIGS. 4 and 5 in a latchedand unlatched condition, respectively; and

FIG. 9 shows a modification of the spring mechanism of FIGS. 4 and 5with the unlatched condition in dotted lines.

Referring now to the drawings wherein like reference numerals are usedto designate like parts and more particularly to FIG. 1 wherein amotor-vehicle seat 2 resting on a hinged seat underframe 1, consistsessentially of a seat cushion 3 with a seat-cushion frame 4 receiving abracket 5 which is displaceable in the longitudinal direction of thevehicle and on which a backrest 6 is articulated. The latter is providedwith a headrest 7 adjustable in terms of height and inclination and canbe swung forward in a way described in more detail later, the backrest 6experiencing during the pivoting movement a controlled rearwarddisplacement relative to the seat cushion 3, thereby assuming theposition represented by dot-and-dash lines.

When a lever 8 mounted on the seat underframe 1 is pivoted, a lockinglever 9 located on the floor is disengaged from an associated lockingcatch 10 fixed to the vehicle, the entire seat 2 can be moved forwardabout a front pivot axle 11 into its position represented by brokenlines, in which the seat underframe 1 assumes an extended position, thusproviding a large passage width, so that, in particular, a convenientpassage to the rear loading space (not shown) from the co-driver's sideis obtained. During this pivoting operation, even when the headrest 7 isfully extended, there is no danger that it will come up against thedashboard 12 indicated, and the centrally arranged casing 13 coveringthe engine (not shown) at the top also does not impede the pivotingoperation.

It can be seen in more detail from FIG. 2, which shows the backrest 6 inits position of use, that the bracket 5 is provided with a guide device14 consisting essentially of a slot 15, into which engages the pivot pin16 assigned to the seat cushion and intended for a lever arrangement 17.The latter consists of a supporting lever 18 which has two portionsarticulated to one another and which at the same end as the backrest isassigned rigidly to the point of articulation 19 of the backrest 6.

The slot 15 also has engaging in it a locking pin 20 which projects fromthe seat-cushion frame 4 and on which engages a spring-loaded lockinglever 21 which is equipped with a rigidly connected locking nose 22offset in the transverse direction of the vehicle and engaged with a pin23. The latter projects from a plate 25 connected rigidly to thebackrest frame 24. Thus, in the position of use of the motor-vehicleseat 2 as illustrated, double locking of the position of the backrest 6is obtained. The locking lever 21 is mounted pivotably on the bracket 5,and a peg 26 projecting from the inner face of the bracket 5 andinteracting with the locking nose 22 limits the pivoting travel. A bentshaft 27 connected rigidly to the locking lever 21 and extending in thetransverse direction of the vehicle is used to transmit the pivotingmovements to a mechanism arranged as a mirror-image on the opposite sideof the seat--as shown schematically in FIG. 6--.

When the locking lever 21 is swung back as a result of pressure on abutton 28 attached to it, the locking lever 21 is disengaged from thelocking pin 20 and the locking nose 22 is disengaged from the pin 23, sothat the backrest 6 can now be pivoted forward. During this operation,the backrest 6 is supported by means of the two portions of thesupporting lever 18 which are articulated to one another, so that arearward sliding movement of the bracket 5 is superimposed on thepivoting movement executed about the point of articulation 19, and whenthis operation has ended the backrest 6 adopts the tilted position shownin FIG. 3. When the backrest 6 is raised again from this position, thelocking lever 21 and the locking nose 22 engage automatically when theposition of use is reached.

In the embodiment according to FIGS. 4 and 5, where the sequence ofmovements takes place in the described manner, the bracket 5, when thebackrest is lifted up, supports itself at a stop 29 of the toothedsegment 30 pivotally at the seat frame 1. Said toothed segment 30 isfirmly connected with an operating lever 31. An additional toothedsegment 32 engages with the first segment 30. Said additional segment 32is equipped with a follower pin 33. Said follower pin 33 engages aspring 36 in window 35 arranged on the top side of a connecting rod 34wherein the lower end of the connecting rod 34, loaded by the spring 36in downward direction, is coupled at the locking lever 9 on the floor.

The operation of their locking lever 9 can be seen in FIGS. 7 and 8wherein the elements of FIGS. 4 and 5 are referenced with a subscript"a". Therein first segment 30(a) rotates additional segment 32(a) andfollower pin 33(a) which cams the bottom spring retainer upwardly tolift connecting rod 34(a) from the latched position of FIG. 7 to theunlatched position of FIG. 8. Lifting of the connecting rod 34(a) causesrotation of locking lever 9(a) due to the offset pivot connectionbetween the rod 34(a) and the lever 9(a). FIG. 9 shows an alternativespring mechanism for locking latch 9 with the elements of FIGS. 4 and 5being referenced by a subscript "b". In this arrangement, when pin 33(b)is at right angles to the axis of connecting rod 34(b), the lockinglever 9(b) is in its latched position with the spring 36(b) in a neutralunstressed condition. Rotation of additional toothed segment 32(b) byfirst toothed segment 30(b), causes pin 33(b) to compress spring 36(b)and force connecting rod 34(b) downward. As connecting rod 34(b) ispivotally connected to locking lever eccentrically at the left of thisFIG. 9, the loading lever 9(b) will rotate counter clockwise to thedotted unlocked position.

When the operating lever 31, as shown in FIG. 5, is swivelled upwardagainst the force of the spring 36, the stop 29 disengages from thebracket 5, and by means of the simultaneously occurring upward movementof the connecting rod 34, the locking lever 9 swings to the right, sothat the backrest 6 can be swivelled to the front and the seat frame 1can be folded in.

During a movement of the bracket 5 toward the rear, the stop 29, in aprestressed condition, rests against the bottom side of the bracket 5 inorder to, at the end of a movement in the opposite direction, for thechanging of the motor vehicle seat into its condition of use by anautomatically occurring swivelling, cause a supporting of the bracket 5as well as a pivoting of the locking lever 9 into the locking position.

The pivoting movement caused by the operating lever 31, in a manner thatis not shown, via a shaft extending in transverse direction of thevehicle, is transmitted to a locking arrangement on the other side ofthe seat that is arranged in a mirror-inverted manner, said lockingarrangement affecting at least the assigned bracket.

While I have shown and described two embodiments in accordance with thepresent invention, it is understood that the same is not limited theretobut is susceptible to numerous changes and modifications as known to onehaving ordinary skill in the art, and I therefore do not wish to belimited to the details shown and described herein, but intend to coverall such modifications as are encompassed by the scope of the appendedclaims.

I claim:
 1. A motor-vehicle seat with a backrest which can be swungforward out of the position of use and which is mounted so as to bepivotable forwardly about a lateral pivot on a bracket connected to aseat-cushion frame, there being a guide device by means of which thepoint of pivoting of the backrest on the bracket is displaced rearwardlyrelative to the seat-cushion frame and in the longitudinal direction ofthe vehicle via a lever arrangement connected to the backrest,characterized in that the guide device is assigned to the bracket insuch a way that the latter is arranged so as to be displaceable relativeto the seat cushion frame, and in that, when the backrest is pivoted outof the position of use, the backrest together with the bracket is movedto the rear via at least one supporting lever articulated on the seatframe and fixed to the backrest, and where the bracket in the positionof use is locked against an unintended shifting and supports itself in aprestressed condition at a stop face of a toothed segment that ispivotable at the seat frame and that an additional toothed segmentengages with the toothed segment, the pivotal movement of saidadditional toothed segment, via a connecting rod, being transmitted to alocking lever pivoted on the frame.
 2. A motor vehicle seat according toclaim 1, characterized in that the pivotal movement of the first toothedsegment is transmitted via a shaft extending in transverse direction ofthe vehicle, to a locking arrangement on the other side of the seatarranged in a mirror-inverted manner.